1. Field of the Invention
The present invention relates to a semiconductor device and to a method for fabricating a semiconductor device using the same. More specifically, the present invention relates to an apparatus for cleaning a semiconductor wafer and to a method for cleaning a wafer using the same.
2. Description of the Related Art
Semiconductor devices are ordinarily cleaned using cleaning solutions such as standard cleaning 1 (a mixed solution of hydrogen peroxide, ammonium hydroxide and deionized water), hydrofluoric acid (HF) and a sulfuric peroxide mixture (SPM). These conventional cleaning solutions contain strong chemicals that cause corrosion of a metal layer of the semiconductor device. Therefore, it is necessary to develop new cleaning solutions with the cleaning ability of the conventional solutions but which minimize corrosion of the metal layer.
Ozone water, hydrogen water, and electrolytic-ionized water have recently been studied as cleaning solutions capable of meeting this need. The ozone water and the hydrogen water cleaning solutions are used by dissolving an ozone gas or a hydrogen gas, respectively, that occurs as a result of electrolyzing deionized water, in the deionized water. The electrolytic-ionized water cleaning solution is used by oxidation water and reduction water that occur as a result of electrolyzing deionized water. In the ozone water, the hydrogen water, and the electrolytic-ionized water, it is advantageous to comparatively free control pH and oxidation-reduction potential by using a gas dissolved in the solution or by an electrolytic current during electrolysis. The ozone water, the hydrogen water, and the electrolytic-ionized water can each remove impurities without corrosion of the metal layer using pH and oxidation-reduction potential.
However, the cleaning ability of the ozone water, the hydrogen water, or the electrolytic-ionized water is minor when used at a normal temperature. Raising the temperature of the ozone water, the hydrogen water, or the electrolytic-ionized water increases its cleaning ability. However, if the ozone water, the hydrogen water, or the electrolytic-ionized water is heated for too long or left alone in the opened state, gases in the cleaning solution evaporate shortening the lifespan of the cleaning solution. Also, because heating the ozone water, the hydrogen water, or the electrolytic-ionized water for a long time dramatically reduces its cleaning ability, it is necessary to heat the cleaning solution rapidly, and to use the heated cleaning solution immediately after heating to clean the wafer.